Surgical treatment of Type 2 diabetes – Metabolic Surgery
T2DM – An Asia Problem
Obesity and type 2 diabetes mellitus (T2DM) are an ongoing health-care problem worldwide. Both diseases are closed
related and very difficult to be controlled by current medical treatment, including diet, drug therapy and behavioral
modification. In Asia, T2DM is a more important epidemic health problems than obesity. It was estimated that T2DM
affecting more than 150 million peoples worldwide and expected to be doubled by the year 2025. However, more than
half of the patients are Asian, including 31.7 million diabetes patients in India and 20.8 million diabetes patients
in China while only 17.7 million patients in the USA. Numerous studies have demonstrated the high levels of metabolic
risk factors at relatively low levels of BMI among Asian population because of more prone to have central obesity.
There is an urgent need for prevention and treatment of T2DM in this region.
Gastrointestinal Surgery & Diabetes
Gastrointestinal surgery, such as bariatric surgery, is the most powerful ammunition for obesity treatment. There are
also strong evidences that bariatric surgeries can improve and even cure most of the associated T2DM in morbidly obese
The mechanism for T2DM resolution after bariatric surgery is intriguing. On one hand, a, sustained weight reduction
plays the key mechanism on long-term effect of resolution of T2DM. Weight & fat reduction significantly improve the
insulin resistance in T2DM patient which improves the glucose control. However, change of physiology of gastrointestinal
tract also plays an important role in DM improvement. Gastrointestinal surgery may affect gastric emptying rate, proximal
gut absorption and distal small bowel transit time. Recent studies suggested that these change may alter the gut hormone
release, such as ghrelin, GLP-1, GIP and PYY, which are important hormone involve in glucose control. Moreover, recent
researches had also showed that modulation of gastrointestinal neuronal electric signal will also affect satiety and
What is Metabolic Surgery
The difference between bariatric surgery and metabolic surgery is subtle. Usually we define Metabolic Surgery as
if the primary aim of surgery is for diabetes control / remission (including non-morbidly obese patients), while
Bariatric Surgeries are primarily for weight reduction (include only morbidly obese patients). Although traditional
bariatric surgery for morbidly obese patients (patient selection) with diabetes are well accepted treatment
option, application of these surgeries to NON-MORBID OBESE (BMI < 30) and use of NEW PROCEDURE in diabetic patients should
not be taken lightly. These procedures are still considered as EXPERIMENTIAL as there are still insufficient data
regarding its safety and effectiveness, especially in long term. When patients are going to receive metabolic surgery,
it should be conduct under a professional Institute Review Board (IRB) approved protocol with adequate explanation and
follow up in order to protect both the patients and physician about the unknown effect and long-term sequels.
Consensus on Metabolic Surgery in Asia
In August 2008, fifty-two professionals involved in the field of bariatric surgery, metabolic surgery, diabetes and medical
research from countries across Asia were met at India. A Consensus was drawn during the meeting and these recommendations
are endorsed by the Asia-Pacific of Metabolic and Bariatric Surgery Society (APMBSS) and the Asia-Pacific Chapter of
International Federation of Surgery of Obesity (IFSO) regarding the use of surgery as treatment of obesity and diabetes.
Metabolic surgery should be considered as a treatment option for obesity in people with Asian ethnicity with a BMI more than
35 kg/m2 with or without co-morbidities.
Metabolic surgery should be considered as a treatment option for obesity in people with Asian ethnicity above a BMI of 32 with
Metabolic surgery should be considered as a treatment option for obesity in people with Asian ethnicity above a BMI of 30 if they
have central obesity (waist circumference more than 80 cm in females and more than 90 cm in males) along with at least two of the
additional criteria for metabolic syndrome: raised triglycerides, reduced HDL cholesterol levels, high blood pressure and
raised fasting plasma glucose levels.
Any surgeries done on
diabetic patients with a BMI less than 30 kg/ m2 should be strictly done only under study protocol with an informed
consent from the patient. The nature of these surgeries should be considered as yet purely experimental.
Metabolic surgery – Possible options
Traditional bariatric surgery
Application of traditional restrictive surgery (e.g. adjustable gastric banding, sleeve gastrectomy) and malabsorptive procedure
(gastric bypass, biliopancreatic diversion) will induce weight loss and hence improve diabetic control. The surgical risk and degree
of DM improvement may be different between difference procedures, and patients should be well informing on the pros and cons of these
procedures before surgery. Our center are currently conducting research on the application of surgery in moderate obese (BMI 25-30)
patients with poor control diabetes.
Application of electric stimulation to stomach (e.g. Gastric Contraction Modulator, GCM) and vagus nerve (e.g. Neuro-Blocking)
in achieving weigh reduction and diabetes improvement had been studied in the last few years.
"Gastric Contraction Modulator" is an implantable device which generates electrical pulses to stimulate the stomach muscles.
This device is introduced by laparoscopic technique and works like a pacemaker. It enhances the activity of gastric muscles
during a meal, which activates and modifies the nervous and hormonal signals. The stimulation causes the subject to feel full
sooner, reduce food intake and thus take less food, resulting in weight loss. This is often accompanied by improvement in blood
glucose levels, blood pressure and waist circumference.
Our center had started a clinical trial since 2010, which aims to compare traditional insulin therapy against the use of
"Gastric Contraction Modulator" implant in difficult-to-treat obese T2D patients. Instead of starting insulin injection therapy,
moderately obese patients (BMI 25-30) will receive laparoscopic implantation of this device at the Prince of Wales hospital.
New Bariatric /
Metabolic Surgical Procedures
Apart from traditional bariatric surgery, there are some new innovative bariatric surgical procedures developed in the
recent year which designed to induce metabolic change by manipulation of gastrointestinal anatomy. These procedures
include pure duodeno-jejunal bypass (without gastric diversion), sleeve gastrectomy with duodeno-jejunal bypass, ileal
interposition with or without sleeve gastrectomy and greater curvature plication. Although the initial results of these
procedures are promising, there are still potential surgical risks among these surgeries. The application of these
procedures in diabetic patients is still experimental and the long term safety and efficacy will await further evaluation.